Edwin t



(No Model.)

B. T. GREENPIELD. METHOD OF AND APPARATUS FOR MAKING METAL oovmmn TUBES.

1 No. 469,663. Patented Feb. 23, 1892.

3 awuamqoz llNrrnn STATES PATENT OFFICE.

EDI/VIN T. GREENFIELD, OF NEW YORK, N. Y.

METHOD OF AND APPARATUS FOR MAKENG METAL-COVERED TUBES.

SPECIFICATION forming part of Letters Patent No. 469,663, dated February23, 1892.

Application filed August 25, 1891- Serial No.403'7l1. (No model.) 7

of construction being such that the tube is made and simultaneouslycovered with a metal covering at one operation.

In a prior application filed by me in the United States Patent Oflice onthe 14th day of July, 1891, Serial No. 399,4:71, I have described andclaimed a novel method of and apparatus for covering tubes with metal bydrawing the tube through a forming-die composed of a series of diesunited together for folding a double-lap joint around the tube as it isdrawn continuously forward. That application is directed, also, to animproved method of and apparatus for making metal tubes in a similarmanner. The present application is an improvement upon the aforesaidinvention to the extent that by the use of roller-dies, hereinafterdescribed, I am enabled to very materially diminish the friction andsimultaneously increase the speed with which the tubing may be drawnthrough the apparatus. It is also an improvement upon the aforesaidinvention to the extent that I simultaneously form and cover=it.Although the present application is directed particularly tometal-covered tubes and to the novel method of constructing and coveringsuch tubes, the form of die hereinafter described is equally applicableto the preparation of metal-covered cylindrical bodies, such asourtain-rolls or other analogous solid bodies, the mandrel hereinafterdescribed being replaced in that instance by the solid body to becovered in the same manner as described in the prior application abovereferred to. In other words, a moving mandrel, which constitutes thepart to be covered, assumes the position of the fixed mandrelhereinafter described. In the aforesaid application I have described aseries of fixed dies of' different conformation united together in closeproximity to a folding or forming shoe in such manner that as the tubeand metal covering -strip are drawn forward the latter is ultimatelyfirmly bound about said tube and provided at one side with a double-lockjoint or seam.

My invention will be fully understood by referring. to the accompanyingdrawings, in Which Figure 1 represents a side elevational View of theentire apparatus, showinga tube in the act of being constructed andsimultaneously covered with a coating or sheathing of metal. Figs. 2 to6, inclusive, are detail views of the dilferent portions of the foldingor forming dies. Fig. 7 is a cross-sectional View of the tube withoutthe exterior metal covering, showing how the strips of paper as they areformed into a cylindrical tube are caused to break joints.

Referring now to the drawings in detail, F, F, and F represent hollowcylindrical form in g-shoes adapted to give to the several strips ofpaper S, S, and S a curvilinear shape about the forming-mandrel M, whichis attached to a fixed support (not shown) and extends to a pointbetween the rolls R R where the tube receives its final shape orconformation. The strips of paper S, S, and S are of varying width, thestrip S being slightly wider than S, and S -in turn slightly wider thanS, so

P represents a similar roll of thin metal,

such as brass, having a width sufficient to surround the completed tubeand be formed with extended lips as it passes through the die D D, asshown in Fig. 2, the forming-shoe A giving to it the necessary curvatureand the die D D turning up the lips, as shown. first set of die-rolls RB have their axes at right angles to the body of the die D D, and theledge Z upon the near roll R gives to the extended lip the angular turnshown in Fig. 3. The next pair of die-rolls R B have their axes locatedat right angles to the axes of the The IOO

rolls R R, as do the succeeding pairs of rolls R R R R and theconformation of these rolls is such that as the tube is drawn forwardthe lips are folded under each other and are ultimately compressed intothe position shown in Fig. 6,which illustrates in cross-section thecompleted tube T- as it passes out of the machine, the edges of themetal strip being folded together in the nature of a locked seamextending throughout the length of the tube and parallel with the axisthereof.

I do not limit myself to the specific mechanism herein shown anddescribed for simultaneously making a tube and covering it with metal,as I believe it is broadly new with me to make a tube of paper bydrawing strips of such material through a machine which gives to them atubular conformation and in simultaneously covering the tube thusconstructed with a metal sheathing or coating, and my claims hereinaftermade are directed, broadly, in this particular to such a feature.

Having thus described my invention, what I claim, and desire to secureby Letters Patent of the United States, is-

1. The described method of makinga metal- -covered tube, consisting indrawing two or more strips of paper continuously forward, giving to thestrips as they are thus drawn forward a tubular conformation the oneabout the other, and simultaneously incasing the tube thus completed ina metal casing having a locked seam extending parallel with the axis ofthe tube.

2. The described method of making metalcovered tubes, consisting incontinuously drawing two or more strips of paper in the same directionand causing them to be bound together in tubular form, so that theybreak joints at the union of their edges, and simultaneously coveringthe tube thus completed with a metal casing or sheath having a lockedscam extending parallel with the axis of the tube.

3. The described method of constructing metal-covered tubing, consistingin continuously drawing two or more strips of paper in the direction oftheir length and successively causing them to assumea cylindrical ortubular form and covering the tube thus formed at the same time with ametal sheath or casing having a locked seam extending parallel with theaxis of the tube, substantially as described.

4:. The described apparatus for constructing and simultaneously coveringa tube with metal, consisting of two or more guide-shoes adapted to giveto the material a tubular form, in combination with a fixed die and aseries of die-rolls for giving to the exterior metal coating of thetubealock joint or seam, all of said die-rolls being located exterior tothe tube while it is being formed.

5. One or more forming-shoes, a fixed die, and one or more pairs ofdie-rolls located wholly outside of the tube while it is being formed,substantially as described.

6. In an apparatus for making metal tubes or coatingtubes with metal, acompound drawdie consisting of a fixed die adapted to give to the edgesof the tube a pair of projecting lips, in combination with a series ofpairs of die-rolls located wholly outside of the tube while it is beingformed, each pair of said rolls being adapted to give to the lips adifferent conformation looking to the completion of the tube,substantially as described.

7. In an apparatus for making metal tubes or covering tubes with metal,a forming-shoe adapted to give to the strip of metal a tubularconformation, a fixed die adapted to turn up the edges of thetube,andtwo or more sets of rolls located wholly outside of the tubewhile it is being formed and having varying conformation for folding theaforesaid lips into alock seam or joint, substantially as de- EDWIN T.GREENFIELD. Witnesses:

G. J. KINTNER, M. L. BUTLER.

